The Islamic calendar is based on the year prophet Muhammad ( ) and his fellow Muslims (known as Sahabah, the Companions) emigrated to Madinah in the year 622 C.E. (Christian Era). The emigration took place after thirteen years of persecutions by the disbelievers of Makkah. By the command of God, the Prophet left the city with his companion Abu Bakr Siddique (R.A.) and escaped a death threat by the disbelievers. The event marks the beginning of a second phase of the Islamic movement. It is the phase when Madinah became the center of an Islamic state.

The Islamic calendar is lunar. Each month must begin with the evening when the new moon is sightable by the unaided naked eye. Muslims are obligated to sight the crescent in every country. Different countries may begin the year at different days based on their own sightings. The calendar is called Hijri calendar. The Arabic word Hijrah means emigration.
In North America, major Muslim organizations are working together to produce an Islamic calendar using the scientific data.
The calendar publishers are requested to include major Muslim holidays in their calendars.
The Islamic Months
The names of the twelve Islamic months are as follows:
1. Muharram
2. Safar
3. Rabiul-Awwal
4. Rabi-uthani
5. Jumadi-ul-Awwal
6. Jumadi-uthani
7. Rajab
8. Sha'ban
9. Ramadan
10. Shawwal
11. Dhil-Q'ada
12. Dhil-Hijja